Physical Changes vs. Chemical Changes

Lesson Plan - Get It!

Audio:

Often times, matter undergoes changes.

Matter can change shape, color, temperature, form, and size. When matter experiences some type of change, it is classified as one of two categories:

• physical change
• chemical change

A physical change is when matter changes size, shape, or state of matter. When matter undergoes a physical change, it still retains its chemical properties. Even if it changes states of matter, what it is does not change.

For example, when water turns from a liquid to a solid, it undergoes a physical change. Even though it has turned into ice, it is still water. Other examples of physical change include cutting a pie into parts, molding play dough into a new shape, and wax melting on a candle.

• Can you think of another example of a physical change?

Chemical changes involve the transformation of the chemical properties of matter. This means the change that takes place is more than just a change in the stage of matter; there is a change in the actual molecular structure of matter.

A chemical change results in one type of matter being turned into an entirely different type of matter. Typically, chemical changes cannot be reversed.

Examples of chemical changes include when food is digested in your digestive tract, exploding fireworks, and a nail turning rusty. Each of these examples involves changing matter into something new.

• What is another example of a chemical change?

Continue learning about the differences between physical and chemical changes as you watch Study Jams Physical & Chemical Changes in Matter from Renee Ratcliff:

Now, read the Chem4Kids article, Chemical Changes Versus Physical Changes, for a good explanation of how matter can be changed into something new.

Now that you have learned the difference between a physical and a chemical change, answer the question from the beginning of the lesson.

• What is the difference between mulch and ash?

Mulch is an example of a physical change because the wood has just changed size and shape.

Ash is an example of a chemical change because fire has turned the wood into ash, a different substance.

• Did you answer correctly?

Great! Keep going in the Got It? section!